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Three Dimensional Molecular Imaging for Lignocellulosic Materials

Description: The development of high efficiency, inexpensive processing protocols to render biomass components into fermentable substrates for the sequential processing of cell wall components into fuels and important feedstocks for the biorefinery of the future is a key goal of the national roadmap for renewable energy. Furthermore, the development of such protocols depends critically on detailed knowledge of the spatial and temporal infiltration of reagents designed to remove and separate the phenylpropen… more
Date: June 9, 2011
Creator: Bohn, Paul W. & Sweedler, Jonathan V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Molecular Aspects of Transport in Thin Films of Controlled Architecture

Description: Our laboratory focuses on developing spatially localized chemistries which can produce structures of controlled architecture on the supermolecular length scale -- structures which allow us to control the motion of molecular species with high spatial resolution, ultimately on nanometer length scales. Specifically, nanocapillary array membranes (NCAMs) contain an array of nanometer diameter pores connecting vertically separated microfluidic channels. NCAMs can manipulate samples with sub-femtolit… more
Date: April 16, 2009
Creator: Bohn, Paul W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nonlinear Dynamics of High-Brightness Electron Beams and Beam-Plasma Interactions: Theories, Simulations, and Experiments

Description: According to its original Statement of Work (SOW), the overarching objective of this project is: 'To enhance substantially the understanding of the fundamental dynamics of nonequilibrium high-brightness beams with space charge.' Our work and results over the past three and half years have been both intense and fruitful. Inasmuch as this project is inextricably linked to a larger, growing research program - that of the Beam Physics and Astrophysics Group (BPAG) - the progress that it has made po… more
Date: May 31, 2008
Creator: Bohn, C. L.; Piot, P. & Erdelyi, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impact of transverse irregularities at the photocathode on the production of high-charge electron bunches

Description: The properties of electron beams produced in a photoinjector are strongly dependent on the initial conditions, i.e. the photocathode drive laser shape and its uniformity. We explore the impact of well-defined transverse laser perturbations on the evolution of the electron beam both in configuration and velocity spaces and especially investigate how certain types of perturbations evolve as the beam propagates in the Argonne Wakefield Accelerator facility. Numerical simulations performed with IMP… more
Date: June 1, 2007
Creator: Rihaoui, M.; Bohn, C. L.; Piot, P. & Power, J. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vector diffraction theory and coherent transition radiation interferometry in electron linacs

Description: Electrons impinging on a thin metallic foil produce small bursts of transition radiation (TR) as they cross the boundary from one medium to the next. A popular diagnostic application is found for compact electron bunches. In this case they will emit radiation more or less coherently with an enhancement of the intensity on wavelengths comparable to or larger than the bunch size, generating coherent transition radiation (CTR). Several detailed analytical descriptions have been proposed for descri… more
Date: June 1, 2007
Creator: Maxwell, T. J.; Bohn, C. L.; Mihalcea, D. & Piot, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SciDAC Advances and Applications in Computational Beam Dynamics

Description: SciDAC has had a major impact on computational beam dynamics and the design of particle accelerators. Particle accelerators--which account for half of the facilities in the DOE Office of Science Facilities for the Future of Science 20 Year Outlook--are crucial for US scientific, industrial, and economic competitiveness. Thanks to SciDAC, accelerator design calculations that were once thought impossible are now carried routinely, and new challenging and important calculations are within reach. S… more
Date: June 26, 2005
Creator: Ryne, R.; Abell, D.; Adelmann, A.; Amundson, J.; Bohn, C.; Cary, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Wavelet-based Poisson Solver for use in Particle-In-CellSimulations

Description: We report on a successful implementation of a wavelet based Poisson solver for use in 3D particle-in-cell (PIC) simulations. One new aspect of our algorithm is its ability to treat the general(inhomogeneous) Dirichlet boundary conditions (BCs). The solver harnesses advantages afforded by the wavelet formulation, such as sparsity of operators and data sets, existence of effective preconditioners, and the ability simultaneously to remove numerical noise and further compress relevant data sets. Ha… more
Date: May 13, 2005
Creator: Terzic, B.; Mihalcea, D.; Bohn, C.L. & Pogorelov, I.V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Longitudinal electron bunch diagnostics using coherent transition radiation

Description: The longitudinal charge distribution of electron bunches in the Fermilab/Nicadd A0 photoinjector was determined using the coherent transition radiation produced by electrons passing through a thin metallic foil. The autocorrelation of the transition radiation signal was measured with a Michelson-type interferometer. The response function of the interferometer was determined from measured and simulated power spectra for low electron bunch charge and maximum longitudinal compression. A Kramers-Kr… more
Date: May 1, 2005
Creator: Mihalcea, D.; Bohn, C. L.; Happek, U. & Piot, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Chaotic dynamics in charged-particle beams: Possible analogs of galactic evolution

Description: During the last couple of years of his life, Henry Kandrup became intensely interested in using charged-particle beams as a tool for exploring the dynamics of evolving galaxies. He and I recognized that both galaxies and charged-particle beams can exhibit collisionless relaxation on surprisingly short time scales, and that this circumstance can be attributed to phase mixing of chaotic orbits. The chaos is often triggered by resonances caused by time dependence in the bulk potential, which acts … more
Date: December 1, 2004
Creator: Bohn, Courtlandt L. & /Fermilab, /Northern Illinois U.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Computational Accelerator Physics Working Group Summary

Description: The working group on computational accelerator physics at the 11th Advanced Accelerator Concepts Workshop held a series of meetings during the Workshop. Verification, i.e., showing that a computational application correctly solves the assumed model, and validation, i.e., showing that the model correctly describes the modeled system, were discussed for a number of systems. In particular, the predictions of the massively parallel codes, OSIRIS and VORPAL, used for modeling advanced accelerator co… more
Date: August 27, 2004
Creator: Cary, John R. & Bohn, Courtlandt L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Collective Modes and Colored Noise as Beam-Halo Amplifiers

Description: As illustrated herein, collective modes and colored noise conspire to produce beam halo with much larger amplitude than could be generated by either phenomenon separately. Collective modes are inherent to nonequilibrium beams with space charge. Colored noise arises from unavoidable machine transitions and/or errors that influence the internal space-charge force. Lowest-order radial eigenmodes calculated self-consistently for a direct-current, cylindrically symmetric, warm-fluid Kapchinskij-Vlad… more
Date: August 6, 2004
Creator: Bohn, Courtlandt L
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

EARLY ENTRANCE COPRODUCTION PLANT

Description: The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, … more
Date: January 12, 2004
Creator: Anderson, John; Anselmo, Mark; Berry, Earl; Bohn, Mark; He, Ming; Schrader, Charles H. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

EARLY ENTRANCE COPRODUCTION PLANT

Description: The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, … more
Date: January 12, 2004
Creator: Storm, David; Nongbri, Govanon; Decanio, Steve; He, Ming; Shah, Lalit; Schrader, Charles et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Final Technical Report, 4 March 1998--15 October 2001

Description: This is the final report covering about 42 months of this subcontract for research on high-efficiency CdTe-based thin-film solar cells and on high-efficiency a-Si-based thin-film solar cells. Phases I and II have been extensively covered in two Annual Reports. For this Final Report, highlights of the first two Phases will be provided and then detail will be given on the last year and a half of Phase III. The effort on CdTe-based materials is led by Prof. Compaan and emphasizes the use of sputte… more
Date: October 1, 2003
Creator: Compaan, A. D.; Deng, X. & Bohn, R. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

EARLY ENTRANCE COPRODUCTION PLANT

Description: The 1999 U. S. Department of Energy (DOE) award to Texaco Energy Systems Inc. (presently Texaco Energy Systems LLC, a subsidiary of ChevronTexaco) was made to provide a Preliminary Engineering Design of an Early Entrance Coproduction Plant (EECP). Since the award presentation, work has been undertaken to achieve an economical concept design that makes strides toward the DOE Vision 21 goal. The objective of the EECP is to convert coal and/or petroleum coke to electric power plus transportation f… more
Date: September 15, 2003
Creator: Benham, Charles; Bohn, Mark; Anderson, John; Berry, Earl; Brent, Fred; He, Ming et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

EARLY ENTRANCE COPRODUCTION PLANT

Description: The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which uses petroleum coke to produce at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals using ChevronTexaco's proprietary gasification technology. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, … more
Date: August 21, 2003
Creator: Anderson, John; Anselmo, Mark; Berry, Earl; Bohn, Mark; Bujas, Roko; He, Ming et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Large diffuse halos in time-dependent space-charge potentials with colored noise

Description: We explore the potential impact of colored noise on space-charge-induced halo formation. By coupling particle orbits to parametric resonance, colored noise due to space-charge fluctuations and/or imperfections in the beamline can eject particles to much larger amplitudes than would be inferred from parametric resonance alone.
Date: May 22, 2003
Creator: Sideris, Courtlandt Bohn and Ioannis V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Chaos and collective relaxation in galaxies and charged-particle beams

Description: Both galaxies and charged particle beams can exhibit collective relaxation on surprisingly short time scales. This can be attributed to the effects of chaos, often triggered by resonances caused by time-dependences in the bulk potential, which act almost identically for attractive gravitational and repulsive electrostatic forces. These similarities suggest that many physical processes at work in galaxies, albeit not subject to direct controlled experiments, can be tested indirectly using facili… more
Date: January 1, 2003
Creator: Bohn, Courtlandt; U., /Fermilab /Northern Illinois; Kandrup, Henry E.; U., /Florida; Kishek, Rami A.; O'Shea, Patrick G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Jefferson Lab Sub-picosecond X-ray Program

Description: The kW-class infrared (IR) Free Electron Laser (FEL) at Jefferson Lab had the capability of producing intracavity Thomson scattering of the IR off the electron beam thus producing high average flux, sub-picosecond x-rays. We have measured these x-rays and demonstrated the energy tuneability range from 3.5 keV to 18 keV. The corresponding flux and brightness has been estimated and will be discussed. This year, 2002, the FEL was disassembled and has been reconfigured to produce 10 kW average powe… more
Date: November 1, 2002
Creator: Boyce, J. R.; Benson, S. V.; Bohn, C. L.; Douglas, D. R.; Dylla, H. F.; Gubeli, J. F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Mixing of regular and chaotic orbits in beams

Description: Phase mixing of chaotic orbits exponentially distributes the orbits through their accessible phase space. This phenomenon, commonly called ''chaotic mixing'', stands in marked contrast to phase mixing of regular orbits which proceeds as a power law in time. It is inherently irreversible; hence, its associated e-folding time scale sets a condition on any process envisioned for emittance compensation. We numerically investigate phase mixing in the presence of space charge, distinguish between the… more
Date: September 4, 2002
Creator: al., Courtlandt L. Bohn et
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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